Co-op and condo boards must remain vigilant against all kinds of potential hazards in their buildings; everything from Legionnaires' disease in rooftop cooling tanks to deteriorating pointing on brick facades, to unsecured window-unit air conditioning can be a threat to both health and property.
You can add dirty air vents and ducts to the above as well. Suspect vent work includes central air-conditioning ductwork: building-wide or individual apartment units, dryer vents, and restaurant kitchen vents. The FDNY requires restaurants to have their vented exhaust systems inspected and cleaned every three months -- yet there are no such requirements for residential buildings and units.
Where My Ducts At?
The presence of ductwork pretty much depends on when your building was built. For simplicity’s sake, let’s divide New York City’s residential buildings into three groups: pre-war buildings (constructed prior to 1941); post-war buildings (built after World War II and through the early 1990s); and post-modern buildings (erected since the early 1990s).
Pre-war buildings are unlikely to have building-wide vents. Circulation systems of this type were not included -- if not unknown -- at the time of their construction. Rooms, in particular kitchens and bathrooms, had windows for air circulation. Even common hallways had windows.
After World War II, building styles and designs changed. Architects placed kitchens and bathrooms in interior positions within apartments, eliminating windows and adding ventilation ducts to promote circulation. Interior hallways became completely interior, and were also ventilated by ducts and vents. Air exchange was executed by fans on rooftops that forced circulation. For the most part, air conditioning was still window-based, with combination forced individual room-based HVAC systems entering the picture during the 1970s. Some larger properties had roof-based central air systems.